This invention relates to an air environment control system that revitalizes air and more specifically to the apparatus that removes carbon dioxide and other trace gas contaminates as well as dehumidifies cabin air of aircraft and spacecraft. The new contaminant control system uses rotary fluid contact machines to scrub cabin air and to reprocess liquid absorbent and water for reuse while extracting carbon dioxide and other contaminants.
Liquid amine (methanol amine water solutions) based carbon dioxide and trace gas contaminant removal apparatus and processes for regeneration of air have been used in nuclear submarines for over forty years. Such systems are used to remove carbon dioxide for the breathing air and depend on gravity to process the liquid carbon amine or other liquids and air mixture.
An example of a combustion gas carbon dioxide process and apparatus is disclosed in U.S. Pat. No. 5,318,758. This type of gas process involves towers and other structures that depend on gravity, blowers and pumps to process the gas. Such systems are not simple or compact and do not work in reduced gravity environments such as on aircraft and spacecraft.
The use of alternative absorbent solutions has been disclosed in U.S. Pat. Nos. 4,285,918 and 3,632,519. These patents teach that water solutions of 3-amino-1,2 propanediol and ω-aminomethyl alkyl sulfone have improved performance for carbon dioxide removal in closed environments such as submarines. They address only the removal of carbon dioxide whereas there are a number of other contaminants that must be removed in these closed environments.
Centrifugal liquid and gas processors have been explored as described in the article “The Centrifugal Mass Exchange Apparatus in Air-Conditioning System of Isolated, Inhabited Object and Its Work Control”, by P. A. Barabash, et al, in Proceedings of the 4th European Symposium on Space Environmental and Control Systems, Oct. 21-24, 1991. The article postulates use of a centrifugal apparatus to work with an air-conditioning system in a closed habitat system such as an orbital space station. A single stage system is proposed that keeps air temperature and humidity parameters within limits. The single stage rotor does not anticipate a more staged air process system using contaminant absorbent fluids and acid wash to provide carbon dioxide and other contaminant removal from a cabin air environment.
As can be seen, there is a need for a simple, compact air regeneration system and method for use in aircraft and spacecraft.